When is Anti D given in pregnancy?

When do you need Anti D in pregnancy?

If you discover you are rhesus negative you may be concerned about whether you need Anti D and what problems this may cause for your pregnancy, your baby, or any future pregnancies. If your blood group is positive then this is not a concern, however your clinicians will need to ensure your blood group to help prevent future problems.

What is rhesus negative?

Everyone has a blood group such as A, B, AB, or O.
Blood also has a “Rhesus” factor, which can be:

  • Rh-positive (you have the RhD protein on your red blood cells)

  • Rh-negative (you do not have the RhD protein)

If you are Rh-negative and your baby is Rh-positive, a small amount of the baby’s blood could mix with yours during pregnancy. Your body could then make antibodies against Rh-positive blood. This is called sensitisation.

These antibodies don’t usually affect your current pregnancy, but they can affect future pregnancies by harming an Rh-positive baby’s red blood cells.

Why is Anti D given in pregnancy?

Anti-D (also called Rho[D] immunoglobulin) is an injection that prevents sensitisation by safely removing any Rh-positive cells from your bloodstream before your body reacts to them.  Anti-D protects future pregnancies.

When is Anti D given in pregnancy?

If a blood test has shown that you are Rhesus negative then you will be given Anti D in the following circumstances due to risks of the baby’s blood mixing with yours. This prevents sensitisation and protect future pregnancies:

  • Routine Dose (usually around 28 weeks)

  • After birth (if the baby is Rh positive)

  • If bleeding occurs in pregnancy
  • After certain procedures ie miscarriage surgery, amniocentesis, CVS, ectopic surgery
  • After abdominal injury

Should you have Anti D in early pregnancy?

Many hospitals now do not routinely give Anti-D before 13 weeks for early miscarriage or medical abortion because the risk of sensitisation is very low.

Anti-D may still be recommended before 13 weeks if:

If you’re unsure, ask your healthcare provider.

Where is the Anti D injection given?

Anti-D is usually given as a small injection into the upper arm muscle (deltoid).

Does Anti D have side effects?

Anti-D has been safely used for many years.

Possible mild side effects:

  • Soreness at injection site

  • Headache or low-grade fever

  • Feeling tired

Serious reactions are very rare.

Do I need Anti D after every bleed?

If you are Rh-negative, tell your doctor or midwife every time you have vaginal bleeding during pregnancy. They will decide if Anti-D is needed based on:

  • Stage of pregnancy

  • Amount of bleeding

  • Type of treatment (if any)

For full details on Anti D including current clinical guidelines please see the British Society of Haematology  and the World Health Organisation